Carcinoembryonic antigen (CEA) and other surrogate inflammatory biomarkers in COVID-19

Abstract

It has been two years since the global outbreak of the highly contagious and deadly corona virus disease (COVID-19) caused by SARS-CoV-2 first emerged in China. Since then, various diagnostic, prognostic and treatment strategies undertaken to address the pandemic have been dynamically evolving. Predictive and prognostic role of various biomarkers in COVID-19 has been a subject of intense exploration. We aimed to determine the association of Carcinoembryonic antigen (CEA) and various surrogate inflammatory biomarkers with the severity of COVID-19 disease. This retrospective cohort study was carried out on 98 patients admitted in Jaypee Hospital, Noida with COVID-19 disease. Information regarding demographics, laboratory parameters and clinical history was collected from Hospital Information System. Serum levels of CEA and other biomarkers such as Neutrophil-lymphocyte ratio (NLR), C-reactive protein (CRP), Interleukin-6 (IL-6), Ferritin, and Procalcitonin (PCT) were assessed. Correlation analyses were performed between the parameters and acute respiratory distress syndrome (ARDS) stages. Logistic regression and ROC curve analysis were performed to assess the various parameters for distinguishing COVID-19 patients requiring ICU admission. Mean hospital stay, NLR, CEA, IL-6, CRP, Ferritin (P< 0.0001) and PCT (P =0.01) were significantly higher in ICU patients when compared to general ward patients. NLR, median serum CEA, IL-6, and CRP levels were significantly higher in non-survivor compared to the survivors (P< 0.0001, 0.0341 and 0.0092). CEA correlated well with disease severity based upon ARDS classification and was a better marker to differentiate patient according to ARDS stages (ARDS 0 vs 2 P= 0.0006; 0 vs 3 P< 0.0001; ARDS 1 vs 2 P= 0.0183; 1 vs 3 P=0.0006). The area under the Receiver operating characteristic (ROC) curve for CEA was 0.7467 (95% CI- 0.64885- 0.84459) which revealed the potential of CEA as a biomarker to distinguish COVID-19 patients requiring ICU admission. CEA can be used to predict the severity of COVID-19 associated ARDS as well as patients requiring ICU admission. Along with routine inflammatory biomarkers (NLR, CRP, IL-6, PCT, and ferritin), CEA should be used for early identification of critical COVID-19 positive patients and for assessing prognosis.